Question

The radii of the elements from chromium (Z =24) to copper (Z = 29) are very close to one another. This is due to

• A. lanthanide contraction
• B. the fact that successive addition of d -electrons screen the outer electrons (4s-) from the inward pull of the nucleus
• C. increase in radii due to increase in n is compensated by decrease in radii due to increase in Z
• D. atomic radii do not remain constant but decrease in a normal gradation

Answer 1

Answer: (B)

The radii of the elements from Cr to Cu, however, are very close to one another. This is due to the fact that successive addition of c/-electrons screen the outer electrons (4s -) from the inward pull of the nucleus. As a result, the size of the atom does not alter much in moving from chromium to copper.